Apparatus for mixing fluids

ABSTRACT

1,089,511. Mixing proportionately flowing fluids. P. G. TACCHI. Jan. 15, 1965 [Jan. 22, 1964], No. 2808/64. Heading B1C. [Also in Divisions F1 and F2] In apparatus for mixing two fluids in constant proportions, e.g. cold water and steam, to form hot water, cold water is admitted at 12 to a high pressure chamber 10 and passes through a restrictive by-pass 18 to a lowpressure and mixing chamber 13. A pressure responsive element such as a bellows 35 separates the two chambers and operates a valve member 31 to admit steam from the inlet 27 to the chamber 13, hot water passing out at 46. An additional fluid (e.g. detergent) may be dosed into the hot water through passage 62 by a pumping device comprising a piston 47 attached to the bellows, a dose being injected every time closure of the outlet control valve, e.g. a spray lance, causes equalization of pressure across the bellows. The stroke of the pump at the size of the by-pass restriction are both adjustable; the latter may be done by a thermostatic capsule. The valve member 31 and its seat 63 may be replaced by others of different sizes. In a modification, (see Figs. 3-6, not shown) the pressure-responsive element is a spring-loaded piston and the pumping device comprises a cylinder attached to the piston and cooperating with a fixed plunger.

Jan. 111, 1966 ccl-u 3,228,560

APPARATUS FOR MIXING FLUIDS Filed Oct. 16, 1964 2 Sheets-Sheet 1 //VVENTO? PERCY GEORGE TACCHI A T TORNE Y5 Jan. 11, 1966 P. G. TACCHI 3,228,560

APPARATUS FOR MIXING FLUIDS Filed Oct. 16, 1964 2 Sheets-Sheet 2 //Vl E/VTO/? PERCY GEORGE TACCHI 3,228,5fiil Patented Jan. 11, 1966 3,228,560 APPARATUS FOR MIXING FLUTDS Percy George Tacchi, llridgnorth, England, assignor to Slip International Limited, London, England, a British company Filed Get. 16, 1964, Ser. No. 404,378 Claims priority, application Great Britain, Jan. 22, 1964, 2,808/64 7 Claims. (Cl. 22257) This invention relates to apparatus for mixing fluids and is specifically concerned with apparatus for injecting a relatively small quantity of a secondary fluid into a flow of a primary fluid. For example, the invention is concerned with apparatus which will enable a secondary fluid such as a detergent to be injected into water which may be used for washing purposes, the water being used through a hose or spray gun or like means.

The object of the invention is to provide a simple form of apparatus for injecting a secondary fluid into the flow of a primary fluid which can be easily controlled from a position remote from the apparatus.

According to the invention I provide apparatus for injecting a secondary fluid into a flow of primary fluid comprising a hollow body having an inlet for the primary fluid and an outlet for fluid, a pressure responsive device within said body arranged to divide the space within the body into a high pressure chamber and a low pressure chamber, a passage of restricted cross-section extending between said high pressure and low pressure chambers, a pumping device connected to said pressure responsive devices, means connecting the pumping device to a supply of secondary fluid and means connecting the pumping device to the low pressure chamber to pass secondary fluid from the pumping device into the low pressure chamber.

The pressure responsive device may comprise a bellows and the pumping device may be connected to the closed end of the bellows, said pumping device comprising a cylinder and co-operating piston, relative movement therebetween being produced by the movement of the close-d end of the bellows and said pumping device being connected to a supply of secondary fluid for pumping secondary fluid into said low pressure chamber.

According to a specific aspect of the invention, I provide apparatus for injecting a secondary fluid into a flow of a primary fluid comprising a hollow body having an inlet for the primary fluid and an outlet for fluid, a pressure responsive device within said body arranged to divide the space within the body into a high pressure chamber and a low pressure chamber, a passage of restricted crosssection extending between said high pressure and low pressure chambers, a cylinder connected to the body and having a piston working therein which is connected to the pressure responsive device for movement therewith, means connecting the cylinder to a supply of secondary fluid and means connecting the interior of the cylinder with the low pressure chamber to pass secondary fluid from the cylinder into the low pressure chamber.

The apparatus is illustrated in one embodiment in the accompanying drawings, wherein,

FIGURE 1 is a section through one form of apparatus, and,

FIGURE 2 is a plan view.

In the apparatus shown in the accompanying drawings, the hollow body comprises a substantially cylindrical body having an upper part which is connected in fluid-tight manner with a lower part 11 and secured thereto by a plurality of screws 12 and the upper part 10 of the body is provided with an inlet 13 which can be connected to a suitable supply of cold or hot water whilst the lower part 11 of the body is provided with an outlet 14 to which may be connected the end of a hose leading to a jet or spray gun or the like in cases where the apparatus is used for washing purposes.

The base of the apparatus is closed by a plate 15 in the centre of which is an upwardly extending hollow boss 16 forming a bearing for sliding engagement by the lower end of stem 17 which extends axially upwards into the body and has its upper end externally threaded and secured in an axial opening in the lower end of a piston 18.

The piston 18 is slidably engaged within a cylinder 19 formed in the upper wall 20 of the cylindrical body, and at its upper end the cylinder has secured thereto a connection 21 which has a pipe 22 leading to a supply of the secondary fluid, so that the pipe 22 forms the inlet supply for the cylinder 19. The connection 21 includes a screwed plug 23 which screws into the upper end of the cylinder 19 and which has, extending therethrough, an axial passage 24 in which is housed a spring controlled ball valve 25 acting as a non-return valve.

The piston 18 has an axial passage 26 extending therethrough to communicate with the passage 24 through the screwed plug and a further non-return spring controlled ball valve 27 is located within the axial passage 26. Finally, there is a transverse passage 28 extending from the axial passage 26 through the piston to the underside or low pressure side thereof so as to provide a connection via pipe 22 passages 24 and 26 with the interior of the bellows 29.

The bellows 2& has its upper end clamped between an upper plate 36 and a lower plate 31, this lower plate 31 being formed integrally with the piston 18 and the two plates being clamped together by suitable screws to firmly secure the upper end of the bellows 29.

The lower end of the bellows is secured to a ring 32 anchored into an inwardly extending flange 33 in the lower part 11.

With reference to FIGURE 1, at one side the upper and lower body parts have projections 34 and 35 respectively and formed therein is a passage 36 which constitutes the passage of restricted cross-section providing communication between the high pressure space 37 on the one side of the bellows and the low pressure space 38 on the other side or interior of the bellows. At its upper and lower end respectively, the passage 36 is in communication with the spaces 37 and 38 respectively by means of openings 39, 4%) in the wall of the upper and lower body parts respectively.

The upper end of the passage 36 is internally threaded and has engaged therein a screw plug 41, the lower end of which is adapted to project across the opening 39 so that by adjusting the position of the screw plug 31 the operative cross-sectional area of opening 39 can be varied to adjust the restriction on the flow from the high pressure chamber 37 to the low pressure chamber 38 thus varying the differential pressure across the bellows 29.

The extreme upper end of the passage 36 is closed by a plug 42 with a spring 43 acting between this plug and the upper end of the plug 41 to prevent any unintentional rotation of plug 41 during operation of the device.

When used, the inlet 13 of the apparatus is connected to a suitable supply of cold water such as a main supply, or hot water, and the outlet 14 is connected to the remote position where the washing or other operation is to take place. For example, a flexible hose may connect the outlet 14 to a jet or spray gun.

When such jet or spray gun at the outlet is opened up the flow of cold water through the apparatus creates a differential pressure across the bellows 29, resulting in contraction of the bellows to move the stem 17 and piston 18 downwardly so that a quantity of the secondary fluid is drawn into the cylinder 19 and remains therein so long as the jet or spray gun is kept open and there is flow through the apparatus. When the jet or spray gun is closed and the flow through the apparatus ceases the differential pressure disappears and the bellows 29 returns to its original position, resulting in that the piston 18 displaces the quantity of secondary fluid from the cylinder 19 past ball valve 27 and via passage 28 into the chamber 38 where it is mixed with the cold water remaining in the apparatus, and the next time the jet or spray gun is operated the desired quantity of secondary fluid is dispensed along with the cold water.

Thus, where the secondary fluid is a detergent for washing purposes the operator can obtain a quantity of secondary fluid whenever desired by simply momentarily shutting off the jet or spray gun to cause the quantity of secondary fluid to be discharged into the cold water for use when the jet or spray gun is next opened up. Thus, by simple operation of a trigger or valve at the remote point the quantity of secondary fluid can be dispensed into the water as and when required without any significant interruption of the washing or other operation which is being carried out. When the outlet is opened up again the detergent is dispensed with the cold water for a limited period and then, so long as the flow remains uninterrupted, clear water is available for rinsing. Instead of control being by means of valve or like in the outlet, it may equally well be by means of a valve in the inlet supply.

In an alternative arrangement, the piston of the dispenser may be formed in, or provided in, an end wall of the hollow body and the cylinder may be connected to the closed end of the bellows and it should be appreciated that in place of a piston and cylinder, any other form of pumping device may be employed deriving its operative movement from the movement of the bellows.

What I claim then is:

1. Apparatus for injecting a secondary fluid into a flow of primary fluid comprising a hollow body of substantially cylindrical form having an inlet for the primary fluid at one end and an outlet for fluid at the other end, a pressure responsive bellows disposed within the body to divide the interior thereof into a high pressure chamber and a low pressure chamber, there being a passage of restricted cross-section extending between the high and low pressure chambers, a pumping device comprising a cylinder and a piston slidable therein, means connecting said pumping device to the closed end of the bellows whereby movement of said bellows produces relative movement between said cylinder and piston, means connecting said pumping device to a supply of a secondary fluid, and means connecting said pumping device to the low pressure chamber.

2. Apparatus for injecting a secondary fluid into a flow of primary fluid comprising a hollow body having a cylindrical interior, a pressure responsive device disposed within the interior of the body and forming a movable partition extending across the interior of the body transverse to the axis thereof, which partition divides the interior of the body into a high pressure chamber at one end of the body and a low pressure chamber at the axially opposite end thereof, an inlet for the primary fluid into the high pressure chamber, an outlet for the primary fluid, and secondary fluid injected therein, from the low pressure chamber, there being a permanently open passage of restricted cross-section extending through the body, through which fluid flows, from the high pressure chamber to the low pressure chamber, the restriction upon flow created by said passage resulting in a difference in fluid pressure between said high and low pressure chambers and resultant differential pressure acting upon said pressure responsive device causing movement thereof in the direction of said axis, a pumping device, disposed within said body and comprising a cylinder and a piston, means connecting said pumping device to said pressure responsive device whereby movement of said pressure responsive device resultant from said differential pressure causes relative movement between said piston and cylinder, said pumping device having an inlet and discharge, means connecting the inlet of said pumping device to a supply of a secondary fluid and means connecting the discharge of said pumping device to the interior of the hollow body.

3. Apparatus for injecting a secondary fluid into a flow of primary fluid comprising a hollow body having a cylindrical interior, a pressure responsive device disposed within the interior of the body and forming a movable partition extending across the interior of the body transverse to the axis thereof, which partition divides the interior of the body into a high pressure chamber at one end of the body and a low pressure chamber as the axially opposite end thereof, an inlet for the primary fluid into the high pressure chamber, an outlet for the primary fluid, and secondary fluid injected therein, from the low pressure chamber, the body, at one side thereof, having a projection on its wall with a permanently open passage of restricted cross-section extending through the projection and communicating at its end with the high and low pressure chambers through openings in the wall of the body through which passage fluid flows from the high pressure chamber to the low pressure chamber, the restriction upon flow created by said passage resulting in a difference in fluid pressure between said high and low pressure chambers and resultant differential pressure acting upon said pressure responsive device causing movement thereof in the direction of said axis, a pumping device, disposed within said body and comprising a cylinder and a piston, means connecting said pumping device to said pressure responsive device whereby movement of said pressure responsive device resultant from said differential pressure causes relative movement between said piston and cylinder, said pumping device having an inlet and discharge, means connecting the inlet of said pumping device to a supply of a secondary fluid and means connecting the discharge of said pumping device to the interior of the hollow body.

4. Apparatus according to claim 3, wherein the said opening communicating with the high pressure chamber is controlled by a screw plug adjustably mounted in said passage of restricted cross-section, said plug being movable to vary the operative cross-sectional area of said opening.

5. Apparatus for injecting a secondary fluid into a flow of primary fluid comprising a hollow body having a cylindrical interior, a pressure responsive device disposed within the interior of the body and forming a movable partition extending across the interior of the body transverse to the axis thereof, which partition divides the interior of the body into a high pressure chamber at one end of the body and a low pressure chamber at the axially opposite end thereof, an inlet for the primary fluid into the high pressure chamber, an outlet for the primary fluid, and secondary fluid injected therein, from the low pressure chamber, there being a permanently open passage of restricted crosssection extending through the body, through which fluid flows, from the high pressure chamber to the low pressure chamber, the restriction upon flow created by said passage resulting in a difference in fluid pressure between said high and low pressure chambers and resultant differential pressure acting upon said pressure responsive device causing movement thereof in the direction of said axis, a pumping device comprising, a cylinder provided in the end of the body adjacent the primary fluid inlet, a piston connected to the pressure responsive device, whereby movement of said pressure responsive device resultant from said differential pressure causes relative movement between said piston and cylinder, said pumping device having an inlet and discharge, means connecting the inlet of said pumping device to a supply of a secondary fluid and means connecting the discharge of said pumping device to the interior of the hollow body.

6. Apparatus for injecting a secondary fluid into a flow of primary fluid comprising a hollow body having a cylindrical interior, a pressure responsive bellows disposed within the interior of the body and forming a movable partition extending across the interior of the body transverse to the axis thereof, which partition divides the interior of the body into a high pressure chamber at one end of the body and a low pressure chamber at the axially opposite end thereof, an inlet for the primary fluid into the high pressure chamber, an outlet for the primary fluid, and secondary fluid injected therein, from the low pressure chamber, there being a permanently open passage of restricted cross-section extending through the the body, through which fluid flows, from the high pressure chamber to the low pressure chamber, the restriction upon flow created by said passage resulting in a difference in fluid pressure between said high and low pressure chambers and resultant differential pressure acting upon said pressure responsive bellows causing movement thereof in the direction of said axis, a pumping device comprising a cylinder provided in the end of the body adjacent the primary fluid inlet, a piston connected to the pressure responsive bellows, whereby movernent of said pressure responsive bellows resultant from said piston and cylinder, said pumping device having an inlet and discharge, means connecting the inlet of said pumping device to a supply of a secondary fluid and means connecting the discharge of said pumping device to the interior of the hollow body.

7. Apparatus for injecting a secondary fluid into a flow of primary fluid comprising a hollow body of substantially cylindrical form having an inlet for the primary fluid at one end and an outlet for fluid at the other end, a pressure responsive bellows disposed within the body to divide the interior thereof into a high pressure chamber and a low pressure chamber, there being a passage of restricted cross-section extending between the high and low pressure chambers, a cylinder provided in the end of the body adjacent the primary fluid inlet, a piston connected to the closed end of the bellows adjacent the primary fluid inlet, the piston having extending therethrough a passage which provides communication between the interior of the cylinder and the interior of the bellows, which latter forms the low pressure chamber, means connecting the cylinder to a supply of secondary fluid and means connecting the interior of the cylinder to the low pressure chamber.

References Cited by the Examiner UNITED STATES PATENTS 932,386 8/1909 Gross 222129.2 2,372,360 3/ 1945 Cornelius 222129.2 2,417,372 3/1947 Morris 22257 X 2,526,920 10/1950 Wise 222-57 X 2,585,172 2/1952 Reynolds 222129.2

LOUIS J. DEMBO, Primary Examiner.

HADD S. LANE, Examiner. 

1. APPARATUS FOR INJECTING A SECONDARY FLUID INTO A FLOW OF PRIMARY FLUID COMPRISING A HOLLOW BODY OF SUBSTANTIALLY CYLINDRICAL FORM HAVING AN INLET FOR THE PRIMARY FLUID AT ONE END AND AN OUTLET FOR FLUID AT THE OTHER END, A PRESSURE RESPONSIVE BELLOWS DISPOSED WITHIN THE BODY TO DIVIDE THE INTERIOR THEREOF INTO A HIGH PRESSURE CHAMBER AND A LOW PRESSURE CHAMBER, THERE BEING A PASSAGE OF RESTRICTED CROSS-SECTION EXTENDING BETWEEN THE HIGH AND LOW PRESSURE CHAMBERS, A PUMPING DEVICE COMPRISING A CHLINDER AND A PISTON SLIDABLE THEREIN, MEANS CONNECTING SAID PUMPING DEVICE TO THE CLOSED END OF THE BELLOWS WHEREBY MOVEMENT OF SAID BELLOWS PRODUCES RELATIVE MOVEMENT BETWEEN SAID CYLINDER AND PISTON, 